THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

ANDERSON COOPER, CNN ANCHOR: Tonight, we begin with direct evidence that Moammar Gadhafi is killing civilians, slaughtering his own people, and trying to cover it up, hide it from you, trying to hide it from the entire world.

It's happening in the city of Zawiyah. The phone lines are cut there. Cell service is shut down. So is the Internet. Reporters are banned. But, tonight, you will hear what is happening. They're not from some anonymous voice on a bad phone line. You are going to hear it from a British reporter named Alex Crawford of Sky News who got into Zawiyah and spent days there documenting what she calls a massacre.

She arrived there last Friday and immediately witnessed large numbers of protesters marching toward Libyan tanks. A few had pistols, but the vast majority were unarmed. And no one fired as they marched. Then Libyan forces began shooting them down.

(BEGIN VIDEO CLIP)

ALEX CRAWFORD, SKY NEWS REPORTER: At this point, the Gadhafi regime is insisting to reporters in Tripoli that his forces are in control here. Well, this is how he's trying to stay in power.

(GUNFIRE)

CRAWFORD: But the rebels have their own firepower, courtesy of army defectors.

(END VIDEO CLIP)

COOPER: We have more from Alex Crawford in just a moment.

For days, she documented the battle, still believed to be raging right now in Zawiyah. You will also hear from a woman trapped inside another town, Misrata, another city under attack by Libyan government forces.

And we're going to with our Arwa Damon, who spoke exclusively with the resistance leader who now has a huge bounty on his head from Gadhafi. We will also talk with our team of correspondents spread out across Libya.

In the east, opposition forces are fighting back hard with captured weapons, including Katyusha rocket launchers and anti-aircraft artillery. But the Libyan air force is pounding them even harder, hammering them with heavy artillery and airstrikes around Ras Lanuf.

Yet it is in cities farther west where wholesale slaughter is taking place. Several times now, the Gadhafi regime has claimed they have repeated Zawiyah. But those reports were false. And we know that now because of Alex Crawford from Sky News, who was there.

The regime has also said again and again that reporters are free to go wherever they want in Libya to cover the story. That true we know is not true -- that too is not true. Yesterday, reporters in a hotel in Tripoli were told they would be shot dead for merely going up on the hotel roof.

And late tonight, new word that a BBC news team trying to get to Zawiyah was detained for 21 hours, beaten by members of the army and secret police, hooded and subjected to a mock execution. They were finally released and managed to get out of Libya.

So did Alex Crawford, the Sky News reporter who spent three days in Zawiyah, witnessing firsthand the repeated attacks by Gadhafi forces against poorly armed civilians with no military training, Libyan civilians who simply want an end to the rule of Gadhafi.

I spoke to Alex a short time ago. And we're going to play you a lot of the interview, because it clearly shows what Gadhafi is doing to his own people. And remember as you listen to Alex, Gadhafi does not want you to hear what she is saying. He's trying to cover up what's happening in Zawiyah, but thanks to Alex Crawford, he has failed.

(BEGIN VIDEOTAPE)

COOPER: Alex, first of all, you and your crew were able to do what no other reporters in Libya were able to do, actually get into Zawiyah and stay there. How did you get in?

CRAWFORD: Well, I think timing was absolutely critical, Anderson, because we went in on the Friday, on the day of Friday prayers.

And although there had been fighting earlier on that day, there certainly wasn't the massive military ring around the town that there is now. We had to go through several checkpoints to get there, but we managed to -- we were with a very sympathetic person who drove us in.

And as we arrived, there was a huge march going on of several thousand people. So we got out of the car and we just saw this wave of people coming towards us and realized that they were all anti-Gadhafi people. They were all civilians. I didn't see anyone in army fatigues or army uniforms or anything. They were just this huge body of people, children amongst them.

(CROSSTALK)

COOPER: We're looking at the video right now. Essentially, they were marching, it looks like, for the most part unarmed and then just got fired upon.

CRAWFORD: Yes, there were a few people, very few people, I would say about half a dozen people, at the head of the group who had -- one person on the car, for instance, had a pistol. One person who was wandering along the side had Kalashnikov slung over his shoulder.

But mostly, the huge majority were just civilians walking, were unarmed, and they were just chanting anti-Gadhafi slogans and calling on him to leave. They walked -- they were marching towards the military lines that had been set up. A tank was in front of (AUDIO GAP) and a number of military vehicles.

And as they got close, they opened fire. And they didn't just open fire once or twice. And they didn't just fire over them. They fired into them. And the casualties were instant and immediate, and they carried on firing.

COOPER: And we're seeing people run away right now from that firing.

What's so important, not only remarkable about your reporting, but what's so important about it is because pretty much each step of the way, you show evidence, direct evidence, irrefutable evidence that the Gadhafi regime is not telling the truth in many of their public statements.

For instance, they repeatedly say they have not fired on unarmed protesters. You personally witnessed them doing just that.

CRAWFORD: They did not just once, but scores of times. I can't even count how many times they did it over the entire period that we were there.

And we were in Zawiyah for -- from Friday midday until Sunday afternoon. And there was continuous, constant, repeated shelling, firing, bombing, attacking of that town. And the military got closer and closer and got -- basically, it's trying to strangle the town.

And the people inside it, they aren't -- to call them a rebel army is just not the case there. There may be rebels in the east, a rebel -- sort of rebel army made up of this -- defections from the Gadhafi army, but in this town, they are 99 percent civilians.

There are a few soldiers who have defected, very, very few, and they have brought with them some weaponry, but they are vastly outnumbered by the civilians in the town. This is a town that is under siege, being constantly attacked, and there is a massacre going on there.

COOPER: The other lie that the regime has been telling which your reporting again highlights and points out is this claim by Gadhafi and his son and his spokesmen that they're fighting al Qaeda and that al Qaeda has drugged Libyan teenagers with hallucinogenic pills. Again, what you just said shows that to be completely false.

CRAWFORD: I saw no evidence of any al Qaeda either influence or input or anything to do with terrorism at all. The only terrorism appeared to be coming from outside and focusing in on those towns.

Everyone I spoke to -- and there were hundreds of people, thousands who I was mixing and mingling with in the hospital, in the mosque, in town, in the square. Amongst the -- some of the defectors, they are primarily people who live in that town. They're very determined to try and (AUDIO GAP) that there's no al Qaeda influence.

I had a couple of colleagues, journalist colleagues, who were in Tripoli who (AUDIO GAP) network was still up. They were texting me and saying at the moment, they're saying that -- the government spokesman here is saying that they have retaken the town.

And I said, well -- they could hear all the firing in the background of my telephone conversations with them. And it was a complete lie. Later on that day, they said apparently the forces have moved in and they have regained control and they say that you're lying.

At this point, we were under fire, being shelled on -- gunfire all around. It wasn't even just one side. It was top, bottom, left, right, in front, behind, absolutely under attack. And as soon as the government forces pulled back, the place had filled with Zawiyah civilians and residents again.

If they weren't against Colonel Gadhafi before, they absolutely are to a man and woman now. There is no one there who wants him. And the only way that that town can be taken control of by the authorities or the Colonel Gadhafi forces is if they actually took up residence in the town and never left.

COOPER: You also report on something we have heard many reports of, but have not directly seen. You actually were in an ambulance that was fired on by Libyan government forces.

CRAWFORD: Yes. We got -- we ourselves were fired on whilst we were in the ambulance.

At the front of the ambulance, there were two doctors clearly identifiable in green medical gowns. But, also, at the hospital, we have got on film two -- at least two ambulances who came in with bullet holes all the way down one side. The back rear window had been shot out. So the whole of the window was taken out.

And whilst I was there and my crew were there, there were people being unloaded from the ambulance. And the shelling was landing right next to the hospital. They -- the actual doctors and medical staff who were around the stretcher trying to take in this wounded civilian, there were about 25, 30 of them, all (AUDIO GAP) blue medical gowns, green medical gowns, white medical gowns, thought they were being attacked, and scattered.

(END VIDEOTAPE)

COOPER: We're going to have more with Alex in a moment.

Join us on Facebook. Follow me on Twitter at AndersonCooper. I'm live tweeting during the broadcast tonight.

Up next, Alex on Gadhafi's constant claim he's only battling against trained fighters in Zawiyah.

(BEGIN VIDEO CLIP)

CRAWFORD: Ninety-nine percent of them are civilians. They are women. They are children. They are old people. They're not fighters. They're not soldiers.

(END VIDEO CLIP)

COOPER: Later, they're outmanned and outgunned -- a report from the front lines and a look at how Western airpower could change the equation.

(COMMERCIAL BREAK)

COOPER: Well, much of what is happening in Libya threatens to be hidden, unknown. The regime is doing everything they can to make it hard on reporters there, not allowing them to go where they want to.

A BBC crew, as we mentioned, was held for 21 hours, beaten, they say, and even subjected to a mock execution. We have talked to Libyans every night on the phone and they have told us what they have witnessed. But now a reporter from Sky News, Alex Crawford, got into Zawiyah, and stayed through several days of fierce fighting.

At times, she and her team thought they might die. They saw a lot of civilians die, a lot of wounded, too.

Her reporting is direct evidence, gathering evidence that Gadhafi is lying about who he is fighting and how he is doing it.

More now of my conversation with Sky News' Alex Crawford.

(BEGIN VIDEOTAPE)

COOPER: One of the things I found so moving, beyond the injuries and the courage of people who were defending themselves against this onslaught, was them coming up to you and saying, please, please, get these pictures out, please tell our story, because otherwise their deaths will be in vain, and no one will know really the truth about what is happening there right now and continues to happen there right now at this hour.

For you, you used the word massacre. Are you saying what is happening there is a massacre?

CRAWFORD: Well, the true sense of the word massacre is large-scale deaths, right? There are large-scale deaths going on there, and these are primarily -- I mean, seriously, they are -- 99 percent of them are civilians.

They are women. They are children. They are old people. They're not fighters. They're not soldiers. They're just people who are criticizing and who want a change of government. I don't -- if that's not a massacre, I don't know what is.

They actually can't do much to defend themselves. They are (AUDIO GAP) to even leave. They can't even get out of the way of the firing. And they are continuing to be (AUDIO GAP). And that's why, at the end, there was almost constant firing, but one particular brave individual managed to get us out under fire.

And it was so important for them to know that we were going to be able to broadcast the pictures to the world, because as far as Gadhafi authorities are concerned, that didn't happen. The march didn't happen. There aren't tens of thousands of people in Zawiyah who are critical of him, Gadhafi, and they aren't being shelled and they aren't being killed.

And if we hadn't actually had the help and support of these incredibly courageous people, they would still be saying that. But now -- now that the pictures, I would suggest, have put a -- put (INAUDIBLE) to those lies.

They -- how can we make up those pictures? We saw people dying with horrible injuries, and they are civilians. They are -- boys are as old as my son, who is 15. They are young men. I saw one young man who looks he was -- he might be a university student, if he was living in Britain or America.

He had glasses on. He was wearing a T-shirt and jeans. He didn't look at all like a soldier. He was being shown at the last minute as these tanks were rolling into the square how to use a rocket-propelled grenade launcher. And someone was saying, put it on your shoulder, put it on your shoulder. Just try to kneel a bit and just fire.

And he says Allahu akbar and goes off to fight and probably is not alive now. This is -- these are civilians. So, I don't know what -- if that isn't a massacre, I really don't know what is.

COOPER: Well, Alex, I have been just so struck by your reporting over these last several days. And thank you for talking with us. And I'm so glad you're safe. And I'm so glad you have been able to tell the world what is really happening, the truth about what is happening in Zawiyah. Thank you.

CRAWFORD: Thanks for asking me on.

(END VIDEOTAPE)

COOPER: Alex Crawford, who is now in Dubai.

Contrary to government promises, she wasn't free to go wherever she liked to report the story. Neither are Nic Robertson, Ben Wedeman and Arwa Damon. Arwa is in Benghazi. Ben Wedeman is in Brega. And Nic is in Tripoli tonight.

Nic, you were on your way to report from Zawiyah today when you guys were actually turned around by government officials. You had made it there a couple days ago to the outskirts to the Libyan -- on the Libyan government side. And I just want to show our -- remind our viewers some of what you saw over there.

That's a crack, probably not so far from where we are right now. Just taking cover behind this wall, where we're OK.

(END VIDEO CLIP)

COOPER: So, that was on the Libyan government side. They had said they are -- they were in control of Zawiyah. Obviously, as you saw, there was still battle raging.

Do we know what the situation right now in that city? Because Alex Crawford left on Sunday.

NIC ROBERTSON, CNN SENIOR INTERNATIONAL CORRESPONDENT: We really don't have the latest information. It's been almost impossible to get any clear details out of there.

The best we had was when a doctor left the day before yesterday. And we haven't had (AUDIO GAP) since then. It is surrounded. There is -- the electricity we understand has been cut off. Cell phone service is there cut off. So, it's just -- without getting somebody coming out of there now, it's (AUDIO GAP) to know.

What we have seen on state television is pictures of people, Gadhafi supporters, celebrating at sunset last night. It said live and it said Zawiyah now in English on the state TV screens. But we could see from where these people were demonstrating, it wasn't in the center of Zawiyah, where the rebels are. Buildings are slightly taller, several stories, maybe five, six, seven stories high. This was on the outskirts. So even the government's attempts to show they're in control aren't convincing at this stage, Anderson. We just don't know what's happening in the center of the city right now.

COOPER: And all weekend long, the government was saying they had retaken the city. And Alex was hearing that when she was still there with the opposition forces who were still in control of the center of the city.

Arwa, you spoke with an opposition leader today, Abdel Jalil, in Benghazi. The regime has now placed a $500,000 bounty on his head. I want to play some of what he told you earlier.

(BEGIN VIDEO CLIP)

MUSTAFA ABDEL JALIL, HEAD OF LIBYAN NATIONAL COUNCIL (through translator): It has to be immediate action. The longer the situation carries on, the more blood is shed. That's the message that we want to send to the international community. They have to live up to their responsibility with regards to this.

(END VIDEO CLIP)

COOPER: So the leaders in Benghazi, are they saying clear and are they all in agreement that they want a no-fly zone?

ARWA DAMON, CNN CORRESPONDENT: Oh, Anderson, they most definitely do.

And, in fact, there's an increasingly growing level of frustration and anger at the fact that it is taking to long to even implement. They continue to reiterate the fact this is not the time for political debates, this is not the time for bureaucratic red tape.

There are people out there who are dying every day. The opposition can, realistically speaking, only take this battle so far. And, in fact, the international community, global leaders do have a choice to make here. Either they recognize the legitimacy of the National Council, they support the opposition, they put a no-fly zone in place, they take other measures, or, by inaction, they end up supporting Gadhafi, who is a man who, after 42 years of enacting brutal tactics against his own people, is right now wanted by the International Court. That's the choice that the global leaders have to make.

COOPER: And this man actually reached out to President Obama, right? He wrote him a letter?

DAMON: That's right. He did write him a letter around a week ago. He says that they have not received a direct response. They did receive word that the U.S. is trying to get a resolution pushed to -- through the U.N.

We do know that there have been other forms of communication between various opposition leaders and the White House. But at the end of the day, it's still just communication at this stage, and communication is not what these opposition fighters are looking for.

They need action and they need action before their bullets run out. There's a lot of guts, there's a lot of will down at that front line, but they just don't have the military power, the military might to be able to hold off Gadhafi's forces forever.

COOPER: Yes.

DAMON: And the big fear is that if they do begin to get pushed back, you're not dealing with a man who is known to show mercy on those who oppose him -- Anderson.

COOPER: Certainly doesn't have a track record of that.

And coming up, we're actually going to talk to a former -- an admiral who actually years ago flew fighter jets over Libya, North Koreas a lot about their air defenses. And we will talk to him coming up.

But, Ben, at one point a couple days ago, I remember you describing the opposition forces as almost cocky. At this point, what is the situation on the ground? Has their advance toward Tripoli -- I assume that's just been shut down altogether. Are they in retreat? What's the latest?

BEN WEDEMAN, CNN SENIOR INTERNATIONAL CORRESPONDENT: The advance is a thing of the past now, Anderson. What happened today was, they came under intense artillery and missile barrage from the Libyan government forces. They're not quite as cocky as they used to be. We were at the hospital in Ras Lanuf watching as one ambulance after another came out with wounded fighters. One doctor said there's about 25 wounded coming in just the space of a few minutes.

We saw some of those fighters, their comrades out in the parking lot of the hospital basically breaking down. They're really coming under a lot of pressure from the Libyan government forces. The advance has stopped completely. Now the worry is, it's going to start moving the other way, that the Libyan army is simply just softening them up before moving forward.

We did see in the afternoon a lot of rocket launchers, a lot of pickup trucks full of heavy machine guns and anti-aircraft guns moving from the east towards the front. But you have to realize that the other side has tanks, heavy artillery, aircraft, helicopters. It's an uneven fight and it's really starting to show -- Anderson.

COOPER: And how -- obviously, those forces, the opposition forces don't seem militarily organized. Is there a general in command of them? Is there somebody actually sending out orders and they're executing orders or are they just driving up to where they think the front is and kind of deciding what to do then on their own?

WEDEMAN: There are people who are trying to send out orders, but it seems that by and large nobody is listening.

Now, I can't tell you how many times, Anderson, I have seen men, former officers, senior officers in the Libyan army who have come over to the opposition, walking around the front, trying to tell them to stop shooting in the air, to pull back to a better position.

People just don't listen. They will respond: "We're fighting for Libya. God is on our side. We're going up to the front" -- to almost certain death.

So, no, there is not a clear command structure. And, as far as we can tell, there isn't one emerging either, because all of these men at the front, they come in little groups of friends to join the fight. But nobody is directing them -- Anderson.

COOPER: So, Ben, what is to stop Gadhafi's forces from, OK, just marching out to -- going to Benghazi?

WEDEMAN: Well, I think what's stopping them is, on the other hand, this huge enthusiasm, this great determination of these men to fight. It's hard to describe in words the passion they have, the hatred they have for Moammar Gadhafi and their desire to see him go.

They all will tell you the same thing -- 42 years of rule by this man, and they realize one thing, Anderson. If they lose, it's not going to be over, that the reprisals will be brutal and massive and widespread. So, they understand that you either win or something much worse. So I think that's what spurs them on, and that's what may save them is this -- this passion and determination to fight to the bitter end -- Anderson.

COOPER: Nic, do you hear -- from what I'm hearing from Ben is that there's growing concern obviously among the opposition forces, a growing confidence perhaps among the Gadhafi side. Is that what you hear from members of the Gadhafi regime?

ROBERTSON: I think, since the first week of this, where the Gadhafi regime got taken by surprise, they felt confident, because they know what they have got on their side.

They saw themselves losing elements of the army, particularly in the east. And that really worried them. But then the (INAUDIBLE) stopped, and they see what they have. They feel confident that they can count on a lot of tribes. So they do feel confident about this military advance.

I would say perhaps from when it began in earnest late last week, which pretty much when the government here began to realize that the international discussion about a no-fly zone was serious. That (AUDIO GAP) their efforts. Senior officials told me they knew they couldn't sit back and wait to see which way the international community would go, because they needed to use all their military advantages now.

Their assessment is that they can take the towns where Ben is, that they can get within a distance of Benghazi, take all the significant towns west of Benghazi, stop before Benghazi, know that the rebels will then feel that they're -- that they have a lot to lose, and then push the rebels to negotiate.

That seems to be the direction the government is still heading in. It is confident. And it has reason to be because it has that firepower and now it's beginning to see the (INAUDIBLE) -- Anderson.

COOPER: Fascinating, Nic, to hear your reporting that the talk, the international talk about a no-fly zone, even without action on it, just the talk about it, has actually made the Gadhafi regime accelerate their attack to try to get as much as they can before anything might be instituted.

Still ahead tonight, inside Misrata, the site of fierce fighting over the weekend, where opposition fighters beat back Gadhafi forces. No one believes the battle is over, including the young woman you are going to hear from coming up. But she says she has new information about what's happening in Zawiyah. She says she just talked to somebody who got out of there -- her eyewitness account next.

Also, word that NATO is getting closer to a decision on whether to create a no-fly zone over Libya -- new details on that.

(COMMERCIAL BREAK) COOPER: Opposition forces say the town of Mizrata east of Tripoli remains under their control tonight. The streets, they say, are calm for now. But fighting in Mizrata has been fierce in recent days. Bloody clashes over the weekend left dozens dead, dozens wounded, according to a doctor at central Mizrata hospital. He said a 3-year- old child was among those killed.

We want to warn you: this next video is disturbing. The voice narrating it says these are the people who tried to attack the city of Mizrata on March 6. That was on Sunday. CNN cannot independently confirm where or when that video was shot, nor who those people are. They are wearing uniforms. Likewise, we can't confirm witness reports in Mizrata, because we don't have reporters there.

Earlier, I talked to a young woman in Mizrata about what she has seen and what she is bracing for. She also says she has a contact in Zawia and talked about that. For her safety, we're not identifying her.

(BEGIN VIDEOTAPE)

COOPER: I understand you know somebody who just got out of Zawia. What did they say?

UNIDENTIFIED FEMALE: They were just telling us how bad the situation is in Zawia. He had to leave Zawia 30 kilometers out of Zawia just so he could get cell phone reception. He told us that everything has bee cut off: all the sources of communication, telephone services, cell phone. Their electricity has been cut off. Their water has been cut off.

And they're shooting from tanks, from guns, essentially everything. The situation is so unsafe. They're breaking into houses. They're not leaving. Like even children are getting killed. Like, they're not -- the thing is, they're not -- they're not leaving anybody out. Do you know what I mean? They're, like, shooting aimlessly at people, anyone who tries to step up.

I have a friend whose uncle passed away the day before yesterday and they couldn't even get out to bury him because how unsafe the situation is.

COOPER: What is the situation where you are in Mizrata?

UNIDENTIFIED FEMALE: As of today, it's pretty calm. But it's really unpredictable. Like we can't even sleep. Every time we hear a sound, it's like automatically you think it's a helicopter or we think it's firing. So it's really, really, really stressful.

COOPER: There have been repeated attempted by Gadhafi forces to retake Mizrata. At this point, though, they haven't been able to do that?

UNIDENTIFIED FEMALE: No, they haven't been able to do that. But the thing is, so many people in the battle that happened on Sunday, 20 people were killed. One of them was a 2-year-old. A lot of them were civilians. They weren't even equipped with weapons. The number of injured was very, very, very high, like in the 80s.

My brother was at the hospital and he pretty much -- he said that the situation inside the hospitals was a massacre. Like, all the injuries that have been sustained are either to the head and to the neck. So it's obvious that Gadhafi, he doesn't have a limit to who he's killing and how he's killing them.

COOPER: The injuries being to the head and neck, those are wounds -- those are efforts to kill, not to scare away protestors...

UNIDENTIFIED MALE: Exactly.

COOPER: The -- every night on this program, we've been talking about the lies that the regime, the Gadhafi regime has been telling. One of the lies that Saif Gadhafi has been repeating over and over again is that Mizrata is essentially being held hostage.

The people of Mizrata, the third largest city in Libya, some 500,000 people, they're being held hostage by 40 to 50 al Qaeda fighters. That's one of the stories he's been telling. At this point, it's not even necessary to kind of disclaim it. But just in case anyone still might believe what he says, is that what the situation is in Mizrata?

UNIDENTIFIED FEMALE: No, definitely. After 43 years of Gadhafi's lies, anything that comes out of his mouth is pretty much either absurd or a lie. Like we don't even watch his speeches because they'll just -- they just frustrate us so much, because everything he says is a lie.

COOPER: What do you want the world to know about -- about what you need, about what's happening there now?

UNIDENTIFIED FEMALE: I just want the world to know that if they -- what they see on TV is not even half of what's going on. The situation is so unreal. It's horrendous. I mean, what leader of a country brings in people from different countries to kill his own people? How many more people have to die before world leaders like Obama and Stephen Harper actually take a stand?

I mean, condemning what Gadhafi is doing at this point is definitely not enough anymore. Condemning what he's doing while innocent lives are being taken, it's ridiculous. Do the people I love being killed not matter?

It's just -- it's horrific to see what's going on in Libya and to see that people who actually have power around the world are not doing anything about it.

COOPER: Do you -- you know you're taking a risk by making this call?

UNIDENTIFIED FEMALE: Well, I just -- it's the least I can do at this point, because I can't just sit back and watch what's happening without actually doing anything, right? And I mean, at the end of the day, as a Libyan, I just want freedom, and I just want what's best for my country. So by taking this risk, I mean, it's worth it.

COOPER: Stay safe. Thank you for talking to us.

UNIDENTIFIED FEMALE: No problem. Thank you.

(END VIDEOTAPE)

COOPER: A lot of brave people.

Coming up, there are reports that we could hear as soon as tomorrow whether NATO might approve a no-fly zone over Libya. Tonight, we'll look at what that actually would mean. I'll talk to a Navy pilot who has led no-fly operations before. He also led his squadron back in 1986 over that -- in that U.S. bombing mission in Libya. So he's actually flown fighter jets over Libya. He'll talk -- tell us -- tell us about what kind of air defense systems they have.

Later, an update on Egypt. New clashes in Liberation Square, violent clashes, and word that Mohammed ElBaradei, that man, is planning to run for president.

Also, Isha Sesay is following other stories for us tonight -- Isha.

ISHA SESAY, CNN CORRESPONDENT: Anderson, a huge development in Wisconsin tonight in the battle over union bargaining rights. The fight has drawn national attention.

Just hours ago, the bitter stalemate was broken when state senate Republicans found a way to bypass 14 Democrats who fled the state to block the vote. Some are accusing them of choosing the, quote, "nuclear option." Will the battle only escalate? Details ahead.

(COMMERCIAL BREAK)

COOPER: Well, the countdown is on to a possible decision on whether a no-fly zone would be imposed over Libya. We could hear as soon as tomorrow from NATO defense ministers who are scheduled to meet in Brussels to discuss the options.

One key component may be close to falling into place. There are reports that the Arab League may soon voice its support for a no-fly zone.

In the town of Ras Lanuf, in Eastern Libya, Ben Wedeman reports the opposition is getting desperate: outgunned, inexperienced, and under the constant threat of air strikes.

(BEGIN VIDEO CLIP)

BEN WEDEMAN, CNN CORRESPONDENT (voice-over): Ahmed Fatouri (ph) left his clothing store in Benghazi to carry a SAM-7 surface-to-air missile, but he knows he has little chance of hitting one of those planes. He's losing hope that the much-discussed no-fly zone will ever materialize.

UNIDENTIFIED MALE: Just talk. No have any action, just talking.

(END VIDEO CLIP) COOPER: Just talk, he says. There has been a lot of talk about a no- fly zone. We wanted to know how hard would it really be. What would that actually look like?

Joining us live from Princeton, New Jersey, Anne Marie Slaughter, professor of politics and international affairs at Princeton University. She's also former director of policy planning for the State Department.

In Washington, Professor Fouad Ajami of Johns Hopkins School of Advanced International Studies. He's also a senior fellow at the Hoover institution.

And retired four-star Admiral John Nathman. As a naval aviator, harrier commander, he led no-fly operations in Iraq and Bosnia. He was also the lead FA-18 pilot in the 1986 strike on Libya.

Admiral, let me start with you. Just how difficult would it be to establish a no-fly zone over Libya?

ADMIRAL JOHN NATHMAN (RET.), U.S. NAVY: Well, I think that's a great question. I think before we just assume away that a no-fly zone is going to be effective, I think, particularly for the American public, they have to understand, as Secretary Gates has been warning, that this is not a trivial issue.

The first thing you have to do is establish it, and then you have to enforce it. And this -- right now Libya has a current operational, integrated air defense system. And if you want to establish a no-fly zone in Libya, you're going have to locate it; you're going have to target it; and you're going to have to destroy it.

And as Secretary Gates made it clear the other evening in testimony on the Hill, you are attacking Libya to do this.

COOPER: How hard is that to do, I mean, to actually locate that stuff and take it out?

NATHMAN: Well, let me talk about that right now. That's important. You're going to be stripping away critical assets. If you think about it, the big communications intelligence and signals intelligence aircraft primarily come from the United States Navy and the United States Air Force.

Those assets are critical to other strategic theaters, like Afghanistan, Iraq, the western Pacific, particularly what's happening in Korea, and what we see happening right now with Bahrain and the Persian Gulf.

COOPER: But are we talking about a month-long thing to take out assets on the ground?

NATHMAN: Well, you're going to be taking out assets on the ground where you're going to be going after kind of a triad of capability. You're going to be going after command and control assets. You're going to be going after surface-to-air missile systems and anti- aircraft systems.

Many of those systems are mobile. So it may take us a while to locate most of those to make sure that the no-fly zone that we establish is -- can be efficiently patrolled.

Now, part of this is what I'm listening to on the news today, is people are assuming away the no-fly zone is going to fix this particular problem on the ground. If you look at your pictures right now, it's urban conflict. We know who the bad guys are. They're the coalition, they're the forces supporting Gadhafi.

And we know -- we don't know who -- exactly who the good guys are. And if you look at it on the ground, they all look the same. So how are we going to separate out who the good guys and the bad guys are? And just suppressing Migs from flying isn't the answer.

COOPER: Let me bring in Anne Marie Slaughter. You hear the former admiral saying it's an incredibly difficult thing to do. Why, then, do you say that it's essential to do?

ANNE MARIE SLAUGHTER, PROFESSOR, PRINCETON UNIVERSITY: I think the admiral is absolutely right to make clear what it entails. This is not something we undertake lightly. Nor should we think it can -- it will automatically turn the tables.

But we've got a lot of difficult choices here, and the no-fly zone clearly will help some. We're also seeing lots of pictures of aircraft bombing oil installations, bombing people directly.

The people on the ground who are doing the fighting understand that this is -- this isn't boots on the ground. This is just stopping the aircraft. And they think it will make a decisive difference.

From my perspective, we have to try. If we do not try, we are choosing not to act. We don't have a -- you know, there's no sort of just being a bystander here...

COOPER: You're saying that's a choice?

SLAUGHTER: If we don't act, we are choosing not to act, and in the eyes of the Libyan opposition and many across the Middle East, we're basically siding with Gadhafi.

COOPER: You think it would be interpreted as siding with Gadhafi if we don't do something?

SLAUGHTER: I do. Because if Gadhafi retakes these towns and massacres those who are opposed to him, which is what he will do, what the -- what the Libyan opposition will see, what the youth in Egypt and across the Middle East will see, what every Islamic country that have now petitioned the U.N. Security Council for a no-fly zone will see is that we already asked and we did nothing, and Gadhafi won the day.

COOPER: Fouad, there are those who say, "Well, look, what people may see are pictures of civilians, Libyan civilians killed in U.S. air strikes in an attempt to take out, you know, anti-aircraft batteries."

FOUAD AJAMI, PROFESSOR, JOHNS HOPKINS UNIVERSITY: Well, look, I think we've gone through this argument and this idea that somehow or another that America has dirty hands and we are guilty in the Middle East and we can't come to the rescue of these people.

These are very, very weak arguments. And these amazing people that you have put on this show time and again, these simple people, older people, young women who reach out, conquer their fear and speak to us of their dilemma.

The dilemma is that this is a popular uprising against a tyrant, and not only is it this Libyan uprising, by the way, taking after what Ann Marie said, it's also this Arab spring, this Arab awakening, this wider Arab awakening in the region. We must support this awakening. There is no -- there is no alternative.

Nothing happened in the Arab world for decades which has been decent. This is the first decent chance that Arab's had. We have no choice but to support them and protect them against this man.

COOPER: Ann Marie, is there a possibility, though, that if nothing is done, and Gadhafi is victorious or at least doesn't get back Benghazi but gets the rest of the country back, then that sends a message to other dictators in the region that this is how you deal with the opposition, you crush them, move fast against them before the international community can get itself together.

SLAUGHTER: Absolutely. We have been very active, and I think to our credit in Egypt, we pushed very hard, our military did, our diplomats did, on the Egyptian government not to use force. The same in Bahrain. We have upheld the principle of peaceful opposition. If now the one government that has chosen to respond with force gets away with it, other governments will definitely draw their own conclusions.

COOPER: But you know, Fouad, I get a lot of e-mails from people saying, look, why does the U.S. always have to be the only ones doing this? I mean, where are the other Arab states? Why can't they be involved? Where are European countries? Why can't they be involved?

AJAMI: You ask a legitimate question about the Arabs. In a perfect world, in a world where the Arabs are responsible for themselves and for their neighbors, there would be an Arab rescue effort. But no Arab rescue effort is conceivable, and the Libyans know that.

We also asked the same question, by the way, Anderson, a while ago, some generation ago about Bosnia. Why did we have to go to the rescue of Bosnia when it was the backyard of Europe? Why didn't the Europeans do it? The Europeans told us this was the year of Europe at the time. And then in the end, it ended up with America having to do the heavy lifting.

It's the burden of power. It's the burden of being the pre-eminent power in the world. It's the burden of being a moral power in the world. We can't watch this slaughter. And all we are doing is sometimes when we delay intervention, when we delay coming to the rescue, is we just simply, in a way, just postpone the inevitable. We did not go into Bosnia when we should have, and in a way we paid the price for that delay.

The same here. At some point, if the slaughter in Libya becomes intolerable, we're going to be drawn into Libya. So we might as well face -- we might as well do directly what we have to do there.

COOPER: Admiral Nathman, you said it was an integrated air defense system. How sophisticated is the air defense system? What does that actually mean?

NATHMAN: Well, it's a Russian based system. It's actually quite sophisticated; it's coordinated. The Libyans have had it for some time. It's been modernized. They have SA-6 SAM missile systems, which are quite effective.

Let me give you one example for your viewers that should concern you about just assuming a way that we can do a no-fly zone without any effort at all. The most effective electronic attack aircraft in the world is flown by the United States Navy. It's called the FA-18-G. Well, Marine Corps flies just as an effective airplane called the EA- 6-B.

Those aircraft will be needed in scores to effectively suppress the enemy air defenses of Libya. They will have to be either stripped off of current aircraft carriers, out of training or out of Afghanistan. Those aircraft support maneuver schemes for the United States Army, United States Marine Corps in Afghanistan. When they come out, if they come out, we're only going to increase the risk, particularly for improvised explosive devices.

So I want our other guests on the panel to understand that we're going to increase a lot more risk in areas that are probably more strategically important to the United States than Libya.

And I think we have to understand that the president has to make these type of decisions. He's getting the right advice from the chairman and the secretary of defense on this. And he needs to be very careful about these decisions.

COOPER: Very briefly, Anne Marie Slaughter, if you want to respond.

SLAUGHTER: I just want to put this in a larger strategic contest. We are in Afghanistan because we are ultimately fighting al Qaeda. Al Qaeda is a terrorist organization that is fueled by violent extremism across the Middle East.

That larger context, as Fouad pointed out, we now have the greatest chance we have had in a generation to actually help change that narrative so it's no longer about terrorism. It's no longer about victimization. It's actually about democracy, about governments that work. It's about the majority of the people across the Middle East who are under 30. They are the ones watching. This is a part of that struggle, and we -- it will be difficult, but we have to try. It is in our strategic interest as well as our moral interest. COOPER: A lot to think about for our viewers. And we'll see what happens tomorrow if anything actually comes out of this Brussels meeting.

Still ahead tonight, breaking news, controversial news in the battle over the budget in Wisconsin. We'll have the details on that.

Plus, the actor picked to play former vice presidential candidate Sarah Palin in a new movie. Hint: it is one of these three. Find out who it is.

(COMMERCIAL BREAK)

Checking with Isha Sesay for an update on some other stories and a "360 News & Business Bulletin" -- Isha.

SESAY: Anderson, in Cairo, at least 44 people were injured when gangs loyal to Egypt's security apparatus assaulted pro-democracy activists in Tahrir Square. CNN can't independent confirm when this video was shot. It purports to show the attacks.

Meantime, Mohammed ElBaradei, Nobel laureate and former head of the U.N. nuclear agency, said he will run for Egypt's presidency as long as a new democratic system is in place.

And breaking news: Wisconsin's Republican-led state senate has passed Governor Scott Walker's proposed restrictions on collective bargaining for public employees. They got around a Democratic walkout by stripping financial provisions from the bill.

In Arizona, a federal judge entered "not guilty" pleas on behalf of Jared Lee Loughner. The 22-year-old man accused of fatally shooting six people and wounding 13 others, including Congresswoman Gabrielle Giffords. Loughner faces 49 charges related to the mass shooting in Tucson.

NPR's chief executive officer Vivian Schiller has resigned after a series of controversies at the public broadcaster. In the latest incident, NPR's former senior vice president for fund-raising was shown in an undercover video calling the Tea Party, quote, "racist and scary" and questioning whether NPR needs federal funding.

OK, Anderson, it's quiz time for you. Which of these actors will play Sarah Palin in a new film about the 2008 presidential election? Julianne Moore, Tina Fey, or Julianna Margulies?

COOPER: I actually know the answer to this one.

SESAY: You just cheat?

COOPER: No, no. I actually met somebody involved in the production of this a couple weeks ago. Julianne Moore, right? SESAY: Yes, Julianne Moore, you're right. Point for Anderson. The redhead got the role. Julianne Moore will play John McCain's folksy former running mate.

Some may have considered this a bit of a long shot, though. She's not exactly the spitting image of the former Alaska governor. Many may have guessed that, indeed, it would be Tina Fey, that she would have the insight track after her spot-on impersonations of Palin during the campaign.

Were you surprised, Anderson? Because I was.

COOPER: You know, I didn't give it much thought. But I'm sure it will be interesting. I think it's made by the same person who did...

SESAY: "Recount."

COOPER: ... "Recount," yes, which was obviously really well done. So should be great.

SESAY: Yes. You can give it some thought now.

COOPER: All right. More serious stuff ahead at the top of the hour, starting with the video reporting that shows up close, ordinary Libyans being shot down by their own government.